you may have an ulcer, you may be pregnant, you may be nervous, you may have a virus, you may have so many things...is it usually after all meals or certain foods? Are you able to tolerate liquids with no issue? How long have you had these symptoms? Any other associated symptoms?
Digestive enzymes after eating can help. I use Kal-n-zyme gumlets. (They are too big so I cut them in half.) They work wonders for me with this. Peppermint also helps. As does papaya. And they are tasty too.